What type of energy is released during enzyme-substrate interactions?

The correct answer recognizes that during enzyme-substrate interactions, the process results in a decrease in free energy, indicating a spontaneous reaction. This concept aligns with thermodynamic principles where free energy is often described as the energy available to do work within a system. When an enzyme binds to a substrate, the transition from the unbound to the enzyme-substrate complex usually releases energy, leading to a lowering of the overall energy state of the system.

The term "negative free energy" denotes that the reaction proceeds spontaneously and energy is released, driving the reaction toward product formation. This energy release can result from various factors, such as the stabilization of the enzyme-substrate complex or the release of energy due to the formation of new bonds in the product. Thus, the correct answer reflects the concept of energetics in biochemical reactions where association with an enzyme leads to a release of energy, making it thermodynamically favorable.